Isn't it a fairly common thing to not appreciate it when other people get the same reward for no contribution?
It's like when you're a kid and you win some sweets, and your parents decide you have to share them with your little brother. There may be a desire to do so, but does he get half your sweets?
Yes, I would describe that as a pretty common human failing. Human societies are collaborative by nature, and you are likely blind to the situations in which you are "carried" by others, despite being hyper-attuned to situations in which you feel you are "carrying" disproportionate weight. People's lives not being ruined every time they're not useful is a feature, not a bug, of membership in most functioning human groups, and balking at this desirable property when it benefits others is indeed something I associate with children
I've never been a union member, but I've certainly worked with several people I would call "dead weight." Sometimes they've even earned more than me whether through better negotiation or better at office politics. I don't see this as something that only arises when unions are introduced.
